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Exactly how difficult is it to just enter in the current time and move on with your day?
BW
Quick to judge, quick to anger, slow to understand.
Ignorance and prejudice and fear walk hand in hand.
-- Neil Peart
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Well,
It seems you have same problems with me. I install some application "TimeSync" that always synchronize date and time with some server in internet every time i turn on my cellphone. It cost you a penny because you must using GPRS when synchronizing.
The bad side is,TimeSync runs on Windows Mobil cellphone, but i think there's similar application that run on symbian.
"Courage choose who will follow, Fate choose who will lead" - Lord Gunner, Septerra Core
"Press any key to continue, where's the ANY key ?" - Homer Simpsons
Drinking gives me amazing powers of insight. I can solve all the worlds problems when drunk, but can never remember the solutions in the morning. - Michael P Butler to Paul Watson on 12/08/03
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This exactly depends on how they designed the hardware. In some case, the volatile information is stored in something like CMOS as in the case of PC. In other cases, the information is not considered crucial and handled over to user input, as it happens in your handset.
This all is stored in HAL (Hardware Abstraction Layer) or beyond. And you have virtually no mean to reach there, especially in case of low profile controller devices like handsets. Java and other languages stand on builtin OS. They can't reach therein.
________________________________________
To Learn is to Change
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Is all Harddisk PnpDevice?
Thank You.
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:-> It's supposed to be, (PnP means only that the hard disk driver uses the PnP driver architecture, almost every driver uses the PnP driver architecture).
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Hello -
I'm working on a program that scans files on a DVD created by our product (to calculate a CRC).
When using Windows Explorer to copy from the DVD (USB connection) to my C: drive, it takes about a minutes to copy a 1GB file.
My program, however, takes close to ten minutes to read the file (doing nothing else). The following snippet demonstrates the problem:
#define HEAP_SIZE 1000000 // 1,000,000 bytes
static BYTE g_buffer[HEAP_SIZE];
hFile = CreateFile( strThisFile, GENERIC_READ, 0, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
while ( ReadFile( hFile, g_buffer, HEAP_SIZE, &nBytesRead, NULL))
{
++nNumberOfReads;
if ( nBytesRead == 0)
{
break;
}
}Same results are observed when g_buffer is created using HeapAlloc and with varying HEAP_SIZE values.
Any hints as to why I'm seeing this are appreciated!
Thanks.
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Why do you make it hard on the system ?
- files get allocated by sectors and clusters on disk, these are all quantities that equal a power of 2. So a power of 10 for your HEAP_SIZE value is not so good.
- files get cached somehow (the file cache in RAM, and the data cache L1/L2/L3 inside or
close to the CPU chip); the hardware cache has limited size. So it probably is better to
reduce HEAP_SIZE.
I would suggest you try HEAP_SIZE values of 2^15 up to 2^18 (that's NOT C syntax !)
I expect you can get around 50 to 100 MB/s on an average system
And when organized well (two threads, ping-pong), CRC should be free.
Good luck.
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The notion that the block size should be consistent with cluster sizes makes a lot of sense.
However, I tried several sizes (65536, 262140, 1MB, 4MB) all with the same (slow) results using the USB-connected DVD drive (advertised as a "16X").
I did notice something odd, though. Currently using a 4MB block size, I put a breakpoint in my loop and found that if I stepped the program (one or two ReadFile calls per second) that the drive motor sped up.
I added a Sleep(1000) in the loop and found that my read rate went from about 1MB/sec to 4MB/sec (along with increase in motor speed). It's as if blocking on ReadFile is slowing things down. So I may experiment with overlapped IO (new to me as I spend most of my time working on embedded systems stuff).
Thanks.
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Hi,
I missed the "USB connection" in your first post. That will reduce the performance
you might hope to get to less than 40 MB/s. You should be able to reach whatever speed
Windows Explorer gives you when copying a file from DVD to HDD.
Have you tried using a FileStream ?
You could loop reading say 4KB from a FileStream and let Windows worry about the
opmization stuff, it is supposed to make the best of it...
But then, the motor speed observations are surprising. I am not familiar with DVD on USB;
I expect an optical drive to contain a cache capable of holding a couple of tracks, and to preread one track; so if you can transfer a track as fast as the disk rotates I dont
expect particular sounds...
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Haven't tried FileStream yet.
I did stumble on an interesting item: I changed my call to CreateFile thus:
hFile = CreateFile( strThisFile, GENERIC_READ, 0, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL | FILE_FLAG_NO_BUFFERING, NULL);
The FILE_FLAG_NO_BUFFERING flag had a dramatic affect - read speeds in the 18 MB/sec range (block size also makes some difference here).
Thanks for the suggestions - they're what got me thinking.
Regards.
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Hi
CAn any body tell me how to detect the vendor id information from the usb device and
how can i know if drivers are installed for this attched usb device.
Is there any registry entry to be looked up or any device opening and messaging api need to look for.
Anybody has idea Please let me know?
sonani prakash
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Read in the MSDN about SetupAPI.txt (it is located in the Windows directory). You can set in the registry a flag so you would get a lot of information written in to SetupAPI.txt
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hiii m akhshay gandhi....
i m doin engg in information systems
can smbdy help me to connect two computers and process them together i.e parallel processing i have two PCs bbtt hw to do this is strange to me if ne1 can suggest me what to study and hw to do it will be great!!!!!
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kthxbye
Cheers,
Sebastian
--
"If it was two men, the non-driver would have challenged the driver to simply crash through the gates. The macho image thing, you know." - Marc Clifton
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hii Sebastian...
bro i don get ur answer .. can u plz explain...
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Ifuspkinsmsuwlgtitinrtrn
Expands to
if you speak in SMS you will get it in return.
I request all new posters to go through the posting manners and maintain the decorim of this community.
Coming back to your question it is highly vague if you just want to connect two PCs and do data sharing or a Higher level of data processing using parallel processors. Could you please be a bit more clear.
And before you get knocked hard refrain from using SMS
There are only two kinds of people who are really fascinating-people who know absolutely everything, and people who know absolutely nothing.
Oscar Wilde (1854-1900)
Regards...
Shouvik
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I am really sorry for using such short language, i was not aware of it. I don't want to disturb decorim of community.
Actually I want to connect two CPUs and process them together as single. Like Grid Computing.
I really don't understand from where to start for that i need some help.
Thank you sir, I assure you I try my best to maintain dignity of Forum.
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As u r saying it looks you want to chopt down a process into various resorces. But could you please throw some more light on Connecting two CPUs. If you are speaking about grids it is not only based on connection and sharing of two CPUs by a same process but many other resources like bus, ram etc are utilized. Have u given a thought to this.
Also is it you want to build a cluster or a grid please get back to us with the above details.
And bro' it was good u learnt the lesson well. Now it is your duty to pass it on to others 
There are only two kinds of people who are really fascinating-people who know absolutely everything, and people who know absolutely nothing.
Oscar Wilde (1854-1900)
Regards...
Shouvik
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shouvik.d wrote: As u r saying it looks you want to chopt down a process into various resorces.
And bro' it was good u learnt the lesson well. Now it is your duty to pass it on to others
:Cough: :Cough: See here[^]
With respect, I must disagree. A quick look at middle management in just about any corporation shows that the dodo not only survived, it's reproducing in record numbers. Christopher Duncan
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wat to see! It is my own post 
There are only two kinds of people who are really fascinating-people who know absolutely everything, and people who know absolutely nothing.
Oscar Wilde (1854-1900)
Regards...
Shouvik
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shouvik.d wrote: wat to see! It is my own post
Yea, was giving you a hard time about using sms in your post by well referencing your own post which chided that behavior. 
With respect, I must disagree. A quick look at middle management in just about any corporation shows that the dodo not only survived, it's reproducing in record numbers. Christopher Duncan
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Please try to see the context. It was meant as a reply to Akshay's SMS post. well I did get the same bashing from senior members when i was a n00b. now I m catious
There are only two kinds of people who are really fascinating-people who know absolutely everything, and people who know absolutely nothing.
Oscar Wilde (1854-1900)
Regards...
Shouvik
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shouvik.d wrote: well I did get the same bashing from senior members when i was a n00b. now I m catious
I wasn't bashing you, just giving you a hard time (in jest) that's all.
Oh and the post correcting the original poster, was well done.
With respect, I must disagree. A quick look at middle management in just about any corporation shows that the dodo not only survived, it's reproducing in record numbers. Christopher Duncan
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S Douglas wrote: Oh and the post correcting the original poster, was well done
Thanks a lot;)
Keep me burning till the End of Day!!!
There are only two kinds of people who are really fascinating-people who know absolutely everything, and people who know absolutely nothing.
Oscar Wilde (1854-1900)
Regards...
Shouvik
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Poor KID...
But best lesson you gave 
There are only two kinds of people who are really fascinating-people who know absolutely everything, and people who know absolutely nothing.
Oscar Wilde (1854-1900)
Regards...
Shouvik
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